Chapter 4.01

SVG 8800 6” Coat and Develop Tracks

(svgcoat6 and svgdev6)

                                   

1.0         Title

SVGCOAT6 and SVGDEV6

2.0         Purpose

This document has specific information about SVG8800 coat and develop tracks. These tracks are capable of performing in-line prime, coat and develop operations on six-inch wafers (GL4).

3.0         Scope

SVGCOAT6 is a six-inch coat module capable of spinning deep UV resist on the first track and SVGDEV6 is a six-inch develop module capable of spray/puddle develop UV resist and I-line resist exposed wafers on the second track.

4.0         Applicable Documents

Revision History

SVG 8826 Operation Manual available in the Microlab Office.

5.0         Definitions & Process Terminology

5.1         Coat Track: First track (closest to operator) used for prime/coat process steps.

5.2         Develop Track: Second track (furthest from operator) used for develop process.

5.3         In-line Prime Station: First station on the coat track, capable of HMDS prime.

5.4         Hot plates: There are total of four hot plates available on these tracks that are used for prime, soft bake, post exposure-bake and hard-bake process steps.

5.5         Chill Plates: process station following the hot plate designed to cool the wafers.

5.6         Control Panels: Four control panels designed to receive input from the operator.

5.7         Indexer Module: Cassette platforms used for wafer load and unload operations.

5.8         Transport Arms: Arms transfer wafers between stations and/or indexer stations.

5.9         Cybor Pump Control Module: This module controls resist volume, speed and suck back on all our resist lines.

6.0         Safety

Follow general safety guidelines in the lab as well as the specific safety rules as per follows:

6.1         Do not operate the spin coat station with the protection cover off.

6.2         Do not place your hand in the path of track’s moving parts, robots and or indexer module. Never operate the spin or develop modules without the cover.

6.3         Do not access the electronic and high power supplies inside the machine.

7.0         Statistical/Process Data

7.1         Process monitor data on the Microlab’s home page.

7.2         Problem and comment section under the equipment section of the wand.

7.3         Equipment enable message of the wand.

8.0         Available Processes

8.1         Spin Coat Process: The SVG8800 only dispense Rohm Haas UV 210-0.6 Positive DUV Photoresist on six-inch wafers currently.

8.2         Develop Process: There are two types of developers available on SVGDEV6 Track. One of these developers is designed to develop either DUV or I-line photoresist.

8.3         Prime Process: The coat track supports the in-line prime operation at its first station, and just before sending the wafers to spin coat operation.

8.4         Bake Processes: There are total of four bake-stations available on this tool including the one assigned to prime operation. All bake stations except the hard bake can control the temperature within 0.1ºC from the set point.

8.5         Post Exposure Bake is to activate the photo-acid produced during the exposure and making them soluble to the developer solution.  Post-exposure bake and hard bake process steps can be done on the developer track (Track2).

8.6     Hard Bake, controlled by the bottom station in the rightmost display window (Figure 4) is not recommended for small feature, due to possible reflow of the photoresist. UV bake should instead be used (see Chapter 4.21- UVBAKE). This bake station is periodically used for hard baking the bottom anti-reflective (BARC) material at elevated temperature of 200ºC, in which case the developer station is bypassed.

Note:    The hard bake hotplate default setting is 50ºC.  Always return to 50ºC after it has been changed for your desire usage.

9.0         SVG8800 Operation

There are two tracks available on the SVG8800 system. The front track (closest to the operator) is designed to perform prime, spin-coat, and soft-bake operations. The back track is used for post exposure bake, develop and hard bake operations.

9.1         General Coat/Developer Operation

9.1.1                    Enable the system (svgcoat6 or svgdev) on the wand.

9.1.2        Verify that the power to the system is ON.

9.1.3        Verify that desired SVG track (coat or develop) is in AUTO mode. This can be checked on the pertinent control panel (pads) in front of the machine, Figures 1-4 (Appendix 3). The LED next to the word AUTO should be illuminated on the Manual-single-Auto key (switch). If not, press this key to toggle through the other options (SINGLE or MANUAL) until AUTO is selected.

9.1.4                    Select your desired process recipes by first entering your selected program number on the key pad, followed by pressing program select key on the front display.  Alternatively, press the PROGRAM SELECT button on the control panel keyboard to toggle through the available programs (1-9).  When the COATER display is selected successfully, an asterisk appears at the left of the COATER display.  When the OVEN display is selected successfully, a plus sign appears at the left of the OVEN display. 

  Note:  There are four separate display windows: the left two are for coat track, and the right two display windows are for developer track (as shown in Figures 1-4). On the second and the fourth display window (Figures 2 and 4), you can toggle between the two using the STATION SELECT button on the control panel keyboard.  Make sure proper window is activated before entering your desired recipe.

9.1.5                    You will need to change soft-bake or PEB temperature for non-standard programs. Ask a staff to help you, if needed. Make sure to put the temperature back to the DUV photoresist default setting, once done.  The default temperature setting for DUV photoresist is 130ºC.

9.1.6                    Load an empty cassette onto the receive indexer (right side for the coater track, and left side for the developer track). Load the cassette containing your wafers on the send indexer (opposite side from the receive indexer). Make sure that the cassettes are properly seated on the indexers.

Note:    The coater track processes wafers from left to right (first track, closest to operator) and the developer track operates in the opposite direction from right to left, while facing the machine.

9.1.7                    Press the start button on both keypads, designated to each track. This prompts load and receive indexers to go down until the send cassette senses a wafer. The wafer will then be transported to the first station on the track (prime station for the coater and post-exposure bake for the developer track.

Note:    If the receive cassette does not lower, remove the cassette and then replace it. Hit START and the cassette should lower.

9.1.8                    If necessary, press INDEX RESET button once to bring the send indexers up (starting position) or twice for the receive indexer to come up.  (Note that if you press the INDEX RESET button, you must lift the cassettes completely off the elevator and then replace them in order to proceed, i.e. for the cassette to go down.) These actions reset the send & receive elevator and can help user to alleviate/resolve cassette indexer problems.

9.2         Other Functions on the Control Panel

Beside the switch functions described above, i.e. Power, Start, Index Reset, Station Select and Program Select; there are other useful functions, which are described below:

9.2.1                    START INDEX: Depressing the Start Index once, will return the Send indexer to top position. Receive indexer will not reset until any wafer in process enters the receive cassette. Depressing the Start Index twice, will return the Receive cassette to top position immediately unless there is a wafer between the processing station and the receive cassette. The Send cassette is unaffected.

9.2.2                    (PRIME, OVEN, COATER, DEVELOPER) STOP: Ends processing immediately. Pressing START will resume processing with the next operation programmed.

9.2.3                    TRANSFER STOP: Immediately stops all indexers and transfer arms. Wafers in transit between stations will remain in place until START command is given.  Wafers in process will complete processing and will come to the top position waiting for the START command.

9.2.4                    EVENT SELECT: Used to verify the sequence of operations and associate parameters for the selected program. The events will be shown in sequence, but depressing the number followed by the event select key can also access a particular event.

9.2.5                    WAFER LOST:  Allows the operator to resume wafer processing if a wafer is removed or broken during processing or if a sensor fails to see a transfer. The key is only functional when a wafer has not been received at its next station after a 6 sec delay.

9.2.6                    CLEAR: Used to resume processing when machine is in programming, diagnostic or calibration mode. Used to turn off Wafer Lost alarm.

9.2.7                    DIAGNOSTIC SELECT: Used to access machine and sensor state diagnostics. Machine State messages for the send indexer and processing station will be displayed in the upper display window. Machine State messages for the receive indexer are displayed in the lower display window. Sensor State messages are displayed in the top display window only. See Section 4 for a listing of machine and sensor state codes.

9.3         SVGCOAT6 and SVGDEV6 Programs

There are several prime, coat, bake and develop programs are available on these two tracks. The standard DUV resist process is based on the Rohm Haas UV 210-0.6 DUV Positive Photoresist process.

Table 1 - HMDS Prime Programs

Program

(#)

Bake/Prime Temp.

(ºC)

Prime Time

(sec.)

Chill Time

(sec.)

*1

100

60

6

9

No Prime

Table 2 - Spin Coat Programs

Program

(#)

Resist Type

Spin Speed

(RPM)

Nanoduv Measurement Program 10 (RI)

Thickness

(Å)

*1

Rohm Haas UV210 – 0.6

7000

1.56

~ 4200

*2

Rohm Haas UV210 – 0.6

1480

1.56

~ 9000

3

Reserved

8

AZ EBR – link to program 1 to 3

600

9

No Coat

 

Table 3 – Soft Bake Programs

Program

(#)

Bake

Method

Bake Temp.

(ºC)

Bake Time

(sec.)

Chill Time

(sec.)

*1

Proximity

130

60

6

*2

Proximity

130

60

6

3

Contact

90

60

6

9

No Bake

 


 

Table 4 – Post-Exposure Bake Programs

Program

(#)

Bake

Method

Bake Temp.

(ºC)

PEB Time

(sec.)

Chill Time

(sec.)

*1

Contact

130

60

6

*2

Contact

130

60

6

3

Contact

90

60

6

9

No Bake

 

Table 5 - Develop Programs

Program

(#)

Developer Type

Develop Time

(sec.)

Temp.

(ºC)

*1

LDD-26W (Rohm Haas)

45

20

*2

LDD-26W (Rohm Haas)

45

20

3

OPD 4262 (Fujifilm)

60

20

9

No Develop

 

Note 1:    Soft-Bake uses the proximity bake process and Post-Exposure Bake uses the contact bake process for the DUV photoresist. The gap of the proximity bake is about 100 mm.

Note 2:    Developer temperature is at 20 ± 1ºC.

Note 3:    Programs with an asterisk next to the number are standard default programs.

10.0      Troubleshooting Guidelines

10.1      Robot arm problems: Do not touch the robot arms, while they are in motion. This can damage the arms or pinch your fingers, caused bodily harm to the operator.

10.2      Alarm on the track: sensor condition is not satisfied before a certain time has elapsed, then an alarm will sound. The alarm can be turned off by pressing the CLEAR key on the control  panel keyboard. The machine state can then be checked using the diagnostics feature as per follows.

10.2.1      Press the diagnostic select key on the control panel. The display will show the following prompt: SELECT MODE 1-2-3.

10.2.2      Press 1 to display the present machine state.  The  machine state  diagnostic  messages  for  the upstream indexers, and  processing stations are displayed in the upper display window.  Machine state messages for the downstream sensors are displayed in the lower display window.

10.2.3      The following table describes  the  various  machine  state messages and their meanings:

PURGE/EXHAUST FAILURE: Airflow used to purge motors of flammable vapors as a safety feature has been interrupted. Also displayed if process exhaust flow is below minimum acceptable level.

PURGE/EXH RESUMED - START?  Air purge pressure or process exhaust flow is again within limits. Press START to resume operation.

SENDER CASSETTE?                  Designated cassette is no longer detected.

RECEIVER CASSETTE?               By cassette micro switch. Cassette has been dislodged or removed while in process. Replace cassette on support.

SENDER STOP -  START?           When the cassette has been placed.

RECEIVER STOP - START?         On the indexer platform properly, one of these messages will be displayed, Press START to resume operation.

Note:    Cassette can be dislodged if indexer wafer or index sensor does not see wafer, causing indexer to drive past wafer.

CLEAR WAFER - START?            Power-up has been performed with a wafer on the spindle chuck or chill plate: vacuum is turned on momentarily at these locations to check for a wafer. If message is displayed, remove wafer. If no wafer is present, the vacuum sensor needs to be reset to properly detect wafers.

VACUUM BREAK - START?         Vacuum detection of the wafer while it is o